Thorium Isotope Distributions in the Eastern Equatorial Pacific

  • Michael P. Bacon
  • Robert F. Anderson
Part of the NATO Conference Series book series (NATOCS, volume 9)


Measurements of the radiogenic thorium isotopes 234Th 230Th and 228Th in seawater show that all of the isotopes occur mainly in the dissolved form (< 1.0 μm). The fraction of the Th found in the particulate form increases as the radioactive half-life of the isotope increases. We conclude that chemical scavenging of Th in the deep sea occurs by a reversible exchange process and that the rate of exchange is fast compared with the rate of removal of the particulate matter. As a result the suspended particles are nearly equilibrated with the surrounding water with respect to exchange of Th isotopes at their surfaces. This suggests that chemical equilibrium principles may be applicable to the problem of trace metal scavenging in the deep sea.


Earth Planet Isotope Distribution Total Suspended Matter Fine Particulate Matter Woods Hole Oceanographic Institution 
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Copyright information

© Springer Science+Business Media New York 1983

Authors and Affiliations

  • Michael P. Bacon
    • 1
  • Robert F. Anderson
    • 1
  1. 1.Department of ChemistryWoods Hole Oceanographic InstitutionWoods HoleUSA

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